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UI and AI EBU

#1 User is offline   Cyberyeti 

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Posted 2012-January-29, 16:37

Auction proceeds round the table starting with N: NS vul

1----------P-------2(inverted 9+)-3
4(kickback)-4-------P(see below)-P
6---------P---------P---------6
X----------P---------7

N (and the system card) think DOPI is the arrangement
S thinks he's playing DOPE

S has AI that partner has bid 6 opposite no keycards.

S actually has AQJ/AQ in the reds and the Q, N can hardly have a hand where bidding 6 is sensible opposite no keycards, hence he knows a wheel has come off.

Without a question being asked immediately before 6 was bid, there would be no UI. N explains he's expecting to see one ace.

S knows he has UI (but thinks he knows that partner must be expecting one ace for the auction to make sense), and passed 6 worried about a possible losing red suit finesse. When 6 was bid, he thought a man with a possibly winning red K doesn't do that, so bid 7. 7 duly rolls on a finesse.

EW unsurprisingly were unhappy.

How do you sort this one out ?

Edited: Forgot N did X 6
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#2 User is offline   c_corgi 

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Posted 2012-January-29, 17:16

Despit North's failure to make a grand slam try over 4S, South has a ridiculously good hand over the forcing pass of 6S. But why has North not doubled 6S if he thinks they are off a keycard? It seems far-fetched for this to be an attempt to play 6NT (especially since he presumably has the Ace of Spades himself) and it seems likely that it could have been induced by UI or CPU.
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#3 User is offline   ahydra 

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Posted 2012-January-29, 17:24

Meh, too tired to work this out atm - but my first instinct is that the table score should stand for the reasons given in the OP.

ahydra
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#4 User is offline   Cyberyeti 

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Posted 2012-January-29, 18:42

View Postc_corgi, on 2012-January-29, 17:16, said:

Despit North's failure to make a grand slam try over 4S, South has a ridiculously good hand over the forcing pass of 6S. But why has North not doubled 6S if he thinks they are off a keycard? It seems far-fetched for this to be an attempt to play 6NT (especially since he presumably has the Ace of Spades himself) and it seems likely that it could have been induced by UI or CPU.

Sorry, my mistake, N did X 6, amending original post.

N has no UI, so can do what he likes with a forcing pass. He said that in fact he should pass to invite 6N, or indeed bid 6N himself with his actual hand which does indeed contain a stiff A and 7 clubs to the AKJ plus a red king, although I think this is a serious gamble.

I will add this was never put to the test, it was a teams match where the result was not going to be altered by any possible ruling, 6x was going for 1700 anyway, so I merely posted it because I found it interesting.
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#5 User is offline   blackshoe 

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Posted 2012-January-29, 20:14

A question was asked by EW, and answered by North. North has no UI; South has UI from the answer to the question (the answer being, in essence, "South has one key card". In fact, South has two key cards. Could the UI suggest bidding 7 over 6X? I suppose you could argue that since South knows that he has an ace that North doesn't know about, it does. And I would buy that if it were the difference between bidding a small slam and not bidding it. But a Grand Slam is different, particularly when North has doubled 6. So now I'm not sure sure that bidding 7 "could demonstrably be suggested" over pass. If it's not, then the result in 7 should stand.
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Factor in Alzheimers, and I can not recall a bad result from aggessive action in this situation. -- Aguahombre
When I look through the hand records after a club evening, the boards I didn't play are always the ones where I would have done great. -- Cherdano
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#6 User is offline   ahydra 

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Posted 2012-January-30, 05:59

I think the Laws need clarifying. They say you're not allowed to take any action demonstrably suggested by UI. What they don't say is that you're not allowed to take an action that is likely to result in a better score for your side, but some people interpret the former to mean the latter. Then there's "second-order UI" where North has UI that "South has UI and hence has to do such-and-such", etc. It gets ugly.

Here 6SX will clearly net NS a huge plus - but how can South really judge whether 7C will make, let alone net more than 6SX? And what about the AI that if N can bid 6 opposite no keycards, surely 7 makes when South has two? I don't really think we can say that 7C is demonstrably suggested. I guess this is where a poll comes in.

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#7 User is offline   c_corgi 

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Posted 2012-January-30, 07:19

View PostCyberyeti, on 2012-January-29, 16:37, said:


S has AI that partner has bid 6 opposite no keycards.



I don't think this is clearcut. North may have inferred or guessed that South had two KC.


South's argument that he passed 6C because of an expected losing finesse is also unconvincing. North has asked for KC and bid slam facing 0/2 and a potential 9 count without caring about the QC. He presumably holds a very powerful hand with long clubs and 2nd round control in both red suits, so there is unlikely to be an issue regarding location of a red king. It is possible that AQ opposite a singleton needs to play for 2 tricks to make the 13th, but much more likely that there are simply 13 on top (assuming no missing KC). The additional information from the 6S bid only applies to (rare IMO) cases where the finesse was needed for the 13th trick and all it does is increase the chances of the finnesse working from a figure that is around 50% to one that is a bit larger. I think the only tangible reason for South to change his mind regarding whether a grand is on is the UI that clarifies what partner was doing.
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#8 User is offline   blackshoe 

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Posted 2012-January-30, 08:35

View Postahydra, on 2012-January-30, 05:59, said:

I think the Laws need clarifying. They say you're not allowed to take any action demonstrably suggested by UI. What they don't say is that you're not allowed to take an action that is likely to result in a better score for your side, but some people interpret the former to mean the latter. Then there's "second-order UI" where North has UI that "South has UI and hence has to do such-and-such", etc. It gets ugly.


If you violate Law 16 or Law 73C, you are, in theory, subject to a procedural penalty, even if the infraction does no damage. However, you are subject to score adjustment only if there's damage. That's Law 12. The law doesn't need clarifying, although peoples' reading of it may.

Personally, I think the whole "second order UI" argument is a crock, but we've had that thread already.
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I have come to realise it is futile to expect or hope a regular club game will be run in accordance with the laws. -- Jillybean
Factor in Alzheimers, and I can not recall a bad result from aggessive action in this situation. -- Aguahombre
When I look through the hand records after a club evening, the boards I didn't play are always the ones where I would have done great. -- Cherdano
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#9 User is offline   blackshoe 

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Posted 2012-January-30, 08:44

View Postc_corgi, on 2012-January-30, 07:19, said:

I don't think this is clearcut. North may have inferred or guessed that South had two KC.


North said "DOPI", so North thinks South, having passed, has one KC. He has no basis for an inference that South has two. As for "guessing", if he's going to do that, why ask in the first place? If North told me he "knew" South had two KC, he'd have a hard time convincing me he wasn't full of it. If anyone else told me that, well, I'm not buying.
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I have come to realise it is futile to expect or hope a regular club game will be run in accordance with the laws. -- Jillybean
Factor in Alzheimers, and I can not recall a bad result from aggessive action in this situation. -- Aguahombre
When I look through the hand records after a club evening, the boards I didn't play are always the ones where I would have done great. -- Cherdano
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#10 User is offline   c_corgi 

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Posted 2012-January-30, 09:01

View Postblackshoe, on 2012-January-30, 08:44, said:

North said "DOPI", so North thinks South, having passed, has one KC. He has no basis for an inference that South has two. As for "guessing", if he's going to do that, why ask in the first place? If North told me he "knew" South had two KC, he'd have a hard time convincing me he wasn't full of it. If anyone else told me that, well, I'm not buying.


We are at cross-purposes. We know North thinks South has 1 KC, but the problem must be examined from South's perspective. South has no AI to tell him his partner expects 1KC: he thinks North expects 0 or 2. He is contending that North bidding slam implies that North is placing the contract on the basis of his partner having zero KC, which obviously implies a misunderstanding. I am contending that North bidding slam does not imply that he expects his partner to have zero rather than 2 KC.
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#11 User is offline   blackshoe 

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Posted 2012-January-30, 09:30

View Postc_corgi, on 2012-January-30, 09:01, said:

We are at cross-purposes. We know North thinks South has 1 KC, but the problem must be examined from South's perspective. South has no AI to tell him his partner expects 1KC: he thinks North expects 0 or 2. He is contending that North bidding slam implies that North is placing the contract on the basis of his partner having zero KC, which obviously implies a misunderstanding. I am contending that North bidding slam does not imply that he expects his partner to have zero rather than 2 KC.

If North would bid slam even when south is known to have no key cards, then the only possible reason for North to go through KC is to suggest that if South has more than the minimum # of keycards he's shown, he should bid seven. IOW, if North has no interest in a grand slam, he won't KC, he'll just bid six. Therefore, the AI available to South suggests that he should bid seven with two key cards. However, there are two problems with that argument on this hand: first, South also has UI, and "UI trumps AI", and second, South didn't bid seven clubs over six, he bid seven when the opponents bid over six clubs.

Could the UI demonstrably suggest that South bid seven instead of passing six? If so, then when south passed 6, he did not violate Law 16. However, now EW bid 6, which North doubled. This would have been -1700 for EW (so someone said upthread) instead of -920 or whatever, so there would be no damage (but the TD could still award a PP to NS for "use of UI"). However, south did bid 7. The question is whether bidding seven at this point could still demonstrably be suggested by the UI, or whether there is no LA. I don't think that's been established.
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I have come to realise it is futile to expect or hope a regular club game will be run in accordance with the laws. -- Jillybean
Factor in Alzheimers, and I can not recall a bad result from aggessive action in this situation. -- Aguahombre
When I look through the hand records after a club evening, the boards I didn't play are always the ones where I would have done great. -- Cherdano
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#12 User is offline   Cyberyeti 

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Posted 2012-January-30, 09:48

View Postc_corgi, on 2012-January-30, 09:01, said:

We are at cross-purposes. We know North thinks South has 1 KC, but the problem must be examined from South's perspective. South has no AI to tell him his partner expects 1KC: he thinks North expects 0 or 2. He is contending that North bidding slam implies that North is placing the contract on the basis of his partner having zero KC, which obviously implies a misunderstanding. I am contending that North bidding slam does not imply that he expects his partner to have zero rather than 2 KC.

It is 100% certain that N has placed the contract opposite 0. We have a firm agreement that if 2 are required, you sign off in 5 and if partner has 2 he bids 6.

For this not to be the case would require partner to have already shown a very big hand indeed.

And the 1700 would be vs 1390, so +7 instead of +13.
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#13 User is offline   campboy 

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Posted 2012-January-30, 10:10

View PostCyberyeti, on 2012-January-30, 09:48, said:

It is 100% certain that N has placed the contract opposite 0. We have a firm agreement that if 2 are required, you sign off in 5 and if partner has 2 he bids 6.

With that being the case, sounds like you are fine to bid on. In fact if the UI suggests anything it is that 7 is less likely to make since you only have one extra keycard rather than two.
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#14 User is offline   c_corgi 

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Posted 2012-January-30, 10:26

View PostCyberyeti, on 2012-January-30, 09:48, said:

It is 100% certain that N has placed the contract opposite 0. We have a firm agreement that if 2 are required, you sign off in 5 and if partner has 2 he bids 6.



OK. So onto the UI issues.

Initially South passed 6C because he knew something had gone wrong and didnt know what. The UI available by his next turn told him that what had gone wrong was that North thought that they were off precisely one KC because he thinks South has precisely one in his hand. South has a huge hand, so knowing the presence of all the KC (and presumably 2nd round red suit controls) makes it a fairly clear 7 bid IMO (but no more so than on the previous round), but knowledge that all the keycards are held is UI. If the reason South passed over 6C was cold feet and the UI warmed them up that is still UI.
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#15 User is offline   lamford 

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Posted 2012-January-30, 12:20

Let us say that South has something like xx AQJ AQxx Qxxx. Clearly he is very good for an inverted raise. But if he thinks that he is worth Seven Clubs when his partner bid Six Clubs, then he should have bid it on the previous round. I would adjust it back to Six Clubs Six Spades doubled (agreed error), as it looks like a clear use of UI. Unless there is something I am missing. I don't think the fact that an opponent sacrificed makes much difference. And the idea that someone would not have sacrificed with a winning king seems hogwash. How would he have known whether it was right or wrong, for one thing, and, unless there has been a rule change of which I am unaware, one needs two tricks to defeat a slam?
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#16 User is offline   Cyberyeti 

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Posted 2012-January-30, 12:41

View Postlamford, on 2012-January-30, 12:20, said:

Let us say that South has something like xx AQJ AQxx Qxxx. Clearly he is very good for an inverted raise. But if he thinks that he is worth Seven Clubs when his partner bid Six Clubs, then he should have bid it on the previous round. I would adjust it back to Six Clubs, as it looks like a clear use of UI. Unless there is something I am missing. I don't think the fact that an opponent sacrificed makes much difference. And the idea that someone would not have sacrificed with a winning king seems hogwash. How would he have known whether it was right or wrong, for one thing, and, unless there has been a rule change of which I am unaware, one needs two tricks to defeat a slam?

The one thing you cannot do is adjust back to 6, the man that bid 6 was given correct info (card clearly stated D0P1), so that bid must stand, and there was no UI situation created before he bid 6, so if you rule it back, it becomes 6x.

The question is whether you think the 6 bid affects the chances of 7 making.

I did at the table, I reckoned I already knew all the keycards were present at the time I passed 6, I was worried about a losing red suit finesse (we were also 25 up in the match at the time and I didn't want to do anything really stupid), and I thought the odds of having a red suit loser diminished with the 6 bid.
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#17 User is offline   wank 

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Posted 2012-January-30, 13:04

you can write yourself a nice little narrative about why it's right to bid 7 in this situation, but back in the real world if partner had described pass as 0/2/4, as you thought, you'd have passed 6x without thinking too much.
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#18 User is offline   ahydra 

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Posted 2012-January-30, 13:12

Can we not do a poll? "The auction goes <insert auction up to 6C, explaining South's pass as showing even # of keycards>. Your hand is <hand>. What do you bid?" And then, of the people that pass, ask them "OK, LHO bids 6S, partner doubles, now what?" To be 100% fair, the poll really ought to include the state-of-the-match info that South knew about at the time (up 25 imps, standard of opponents / of partner, etc), but I've never had this mentioned when I've been polled on UI situations before.

I wouldn't be surprised to find a lot of people bidding 7C the first time based on "6C = pass if you have 0, bid on if you have 2" or similar. The second time round, however, I don't think the majority of people would bid 7C. But anyway, such a poll at least allows us to determine whether bidding on/pass is an LA on both occasions. Suppose we find pass is an LA the second time, we can probably rule back to 6SX because of the flimsy "might be suggested by the UI" wording of the Laws. As someone mentioned before, this really needs to be changed to "is suggested by the UI".

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#19 User is offline   blackshoe 

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Posted 2012-January-30, 13:35

View Postahydra, on 2012-January-30, 13:12, said:

Suppose we find pass is an LA the second time, we can probably rule back to 6SX because of the flimsy "might be suggested by the UI" wording of the Laws. As someone mentioned before, this really needs to be changed to "is suggested by the UI".

The law does not say this. It says "may not choose from among logical alternatives one that could demonstrably have been suggested over another by the extraneous information". This does not mean "might be suggested". It means that you have to be able to show, via a path of valid logic, precisely how the extraneous information could suggest the alternative chosen. It's not "flimsy" at all, and I don't see that it needs changing. As I said of another proposed change recently, what it needs is education.
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I have come to realise it is futile to expect or hope a regular club game will be run in accordance with the laws. -- Jillybean
Factor in Alzheimers, and I can not recall a bad result from aggessive action in this situation. -- Aguahombre
When I look through the hand records after a club evening, the boards I didn't play are always the ones where I would have done great. -- Cherdano
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#20 User is offline   Cyberyeti 

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Posted 2012-January-30, 13:43

View Postwank, on 2012-January-30, 13:04, said:

you can write yourself a nice little narative about why it's right to bid 7 in this situation, but back in the real world if partner had described pass as 0/2/4, as you thought, you'd have passed 6x without thinking too much.

If partner had described pass as 0/2/4 then bid 6 I'd have been calling for the men in the white coats, it doesn't exist.

I was pretty much aware he'd taken me for 1 when I passed 6 before any UI, as nothing else made any sense. We play D0P1 at the 4 level and DOPE at the 5 level, and was aware at the time I might be wrong when I passed.
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